The two victims were grabbed shortly after 11 p.m. Wednesday from a home in the 14300 block of Ella Boulevard in northwest Harris County. Investigators believe narcotics trafficking may be behind the abduction.

"They (the kidnappers) were trying to recoup some money that was owed to them by a family member" of the victims, Wolfe said.

Harris County sheriff's detectives asked the FBI to join the investigation soon after the victims were taken. About 24 agents and the Houston FBI office's SWAT team worked alongside deputies to track down the hostages and captors.

"We provided analytical, technical and investigative assistance, as well as manpower," FBI Special Agent Shauna Dunlap said. "It was a cooperative effort. It worked out well."

The victims were being held in a one-room apartment added onto the house. Alma Barraza was out with friends when her home security company called and said an alarm had been tripped.

"They asked if I wanted the police and I said, 'Most definitely,' " Barraza said.

Deputies and FBI agents surrounded the house when she arrived. Barraza later learned the alarm had been triggered by the SWAT team.

"They didn't allow me to get in because they said the house was a crime scene," Barraza said. "They asked me if I knew what was going on and I said, 'No.' "

The man who rented the rear apartment had been living there about six months. Barraza said she works all day and wasn't aware that the home had been used by suspected kidnappers.